finding the right connector for I2C

The whole reason I'm looking for something else: I wrote seeed studio about getting the SMT version of the grove connector and they told me that they're sold out / not in stock anymore. I tried a JST 2mm 4 pin connector, but it's just a pain to connect. To be continued, but please, feel free to comment ideas. I need to find a connector that is:

cheap to find / buy

is well supported with modules

easy to connect

shouldn't break stuff if mistaken for something else

easily obtainable cables with no soldering involved

USB

there's already a usb port on the LAMEBOY and I don't want people to mixup stuff

TRRS

would be nice, but I don't want to short stuff by accident or have users mistake it for the headphone plug - especially if there's no audio on board.

Down in the comments Molex adapters and CD rom cables (basically 2.54mm headers) were suggested, I like the hacker-ready approach, but it doesn't feel like a "finished" design that I want to achieve with revision 4. The current boards have the grove connector still on them.

another suggestion from twitter, use spring connectors. interesting, easily plug and play ready and probably accepts pcbs, if done right. using pcbs as connectors is the cheapest thing I can think of :D https://t.co/taDxle3lOT

Yes, it's a bit bigger than RJ-11, for example. I'm just throwing random ideas at you :-) I battled this problem on all my portable computers and found exactly -wait for it - zero solutions. Available connectors are either:

1, Already used (or purposely built) for something (USB, HDMI, RJ45), but small and rugged.

2, Rugged and suitable for generic use, but too big (Cannon, DIN)

3, Small, suitable for generic use, but not rugged enough for daily use (all sorts of pinheaders, edge connectors)

You have connector that is small-rugged-generic, but you can choose not more than two at once. I think this call for connector is similar to your call for keyboard, where you have a few different options and all of them wrong, or at least full of compromises.

Yeah, a backshell would be nice to pretty it up. There's no strain relief with that sort of connector, so the signal wire crimps are the only things holding it together. Best I can think of is to use glue lined heat shrink between the back of the connector and the cable.

SATA is capacitively coupled so it shouldn't destroy the Lameboy or the SATA device if someone does confuse the two.

The other thing is considering how much volume the connector adds to the Lameboy. Right angle SATA and alt-USB are low profile and shallow, while RJ*, DuPont, and TRRS take significant PCB space or height.

If you can find the Wiimote PCB mount connectors, that would be ideal. The Wiimote carries 3.3V power and I2C. And there are prefab controllers out there already...

Maybe you can find some older weird USB connector, like 4-position USB mini B. There were a few very seldom used and nowadays almost nobody uses them, so there is small to none chance of interfering with real devices. There could be a problem with sourcing the connectors, though. It has 4 pins as you need and it you keep connection of 5V (insert schottky diode in series to prevent "backcharge") and GND pins, it will not break everything if you actually connect valid USB peripheral. It is also smaller than RJ11.

When going the RJ11 route, don't forget somebody can plug it to telephone line. You can't do totally foolproof design. Just can't. Never.

I thought about those too, but I think it get's tricky to buy cables then. Right now RJ10 seems nice. I've ordered some sockets in RJ12 / RJ25 size and RJ10 to get a feeling for the size and relations. Maybe